Hypertension-based clinical risk strategies for detecting microalbuminuria in diabetes

• Published in: QJM : An International Journal of Medicine Vol. 98; no. 6; pp. 427 - 433
• Main Authors: Baskar, V., Kamalakannan, D., Kiberd, B., Holland, M.R., Singh, B.M.
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01-06-2005; Oxford Publishing Limited (England)
• Subjects: Albuminuria - etiology; Albuminuria - urine; Antihypertensive Agents - therapeutic use; Biological and medical sciences; Blood Pressure - physiology; Cross-Sectional Studies; Diabetes. Impaired glucose tolerance; Diabetic Nephropathies - diagnosis; Diabetic Nephropathies - etiology; Diabetic Nephropathies - urine; Endocrine pancreas. Apud cells (diseases); Endocrinopathies; Etiopathogenesis. Screening. Investigations. Target tissue resistance; Female; General aspects; Humans; Hypertension - drug therapy; Hypertension - etiology; Male; Medical sciences; Middle Aged; Predictive Value of Tests; Proteinuria - urine; ROC Curve; Endocrinopathy; Hypertension; Medicine; Urinary system disease; Diabetes mellitus; Risk factor; Albumin; Cardiovascular disease; Risk; Strategy; Microalbuminuria; Proteinuria
• ISSN: 1460-2725; 1460-2393
• DOI: 10.1093/qjmed/hci066

Background: Microalbuminuria screening to identify patients at risk of diabetic nephropathy is widely accepted. Aim: To investigate whether blood-pressure-based strategies can identify such patients without the need for microalbuminuria testing. Methods: Spot urine for albumin/creatinine ratios was performed in all patients over an 18-month period. The performance of four combinations of clinical models, based on existing triggers for anti-hypertensive intervention (prior use and/or existing systolic BP exceeding 140 or 160 mmHg and/or dipstick proteinuria exceeding 1+ or 2+) was evaluated at microalbuminuria thresholds of 3.5 and 10 mg/mmol. The models were ranked 1 to 4, based on their escalating relative strengths in predicting need for intervention. Results: Of 3748 patients, 1257 (34%) or 739 (20%) exceeded microalbuminuria thresholds of 3.5 or 10 mg/mmol. All four models predicted microalbuminuria risk (areas under ROC curves 0.60–0.77, all p < 0.001). The models (1–4) identified 2220, 2465, 2803 or 2937 for intervention, respectively, irrespective of microalbuminuria status, and missed 368, 232, 194 or 126 at 3.5 mg/mmol and 164, 87, 81 or 45 at 10 mg/mmol. Discussion: Clinical models using routinely measured parameters reduced the target population for microalbuminuria screening by 60–80%, missing 3–10% of patients with albumin/creatinine ratios exceeding 3.5 mg/mmol or 1–4% of those exceeding 10 mg/mmol.